U.S. Pat. Nos. 3,845,018 and 3,897,349 disclose certain acetylene end-capped polyimide oligomers. Moldings prepared from such resins have excellent physical properties which are largely retained at temperatures as high as 316.degree. C. (600.degree. F.).
The polyimides disclosed in these patents must be prepared from aromatic diamines of specific structures to obtain the desired high temperature performance properties. Unfortunately such aromatic amines are difficult to synthesize and are expensive. In addition, the polyimides are difficult to process.
For the above reasons, there is a need in the art for polyimides having good high temperature performance properties which can be prepared from polyamines that can be more easily synthesized and be made available at lower cost.